Foaming thermoplastic polyurethane resin, producing method thereof, and molded article

ABSTRACT

A foaming thermoplastic polyurethane resin is a reaction product of a polyisocyanate component containing a bis(isocyanatomethyl)cyclohexane and a polyol component. In a peak of chromatogram obtained by measurement of the foaming thermoplastic polyurethane resin with gel permeation chromatography, the area of a high molecular weight component having a weight average molecular weight of 400,000 or more with respect to the total area of the peak is 25% or more and 60% or less.

TECHNICAL FIELD

The present invention relates to a foaming thermoplastic polyurethaneresin, a method for producing a foaming thermoplastic polyurethaneresin, and a molded article containing the foaming thermoplasticpolyurethane resin.

BACKGROUND ART

A thermoplastic polyurethane resin (TPU) is generally a rubber elasticbody obtained by reaction of a polyisocyanate, a high molecular weightpolyol, and a low molecular weight polyol, and includes a hard segmentformed by reaction of the polyisocyanate and the low molecular weightpolyol and a soft segment formed by reaction of the polyisocyanate andthe high molecular weight polyol.

It has been known that the thermoplastic polyurethane resin, along witha foaming agent, is melted and molded, so that a foaming molded articleis obtained.

To be specific, for example, it has been proposed that a pellet of thethermoplastic polyurethane resin is produced from a 4,4′-diphenylmethanediisocyanate (MDI) as a polyisocyanate, a polyester polyol made of anadipic acid and a 1,4-butanediol as a high molecular weight polyol, anda 1,4-butanediol as a low molecular weight polyol, and the pellet, alongwith a foaming agent, is melded and molded, so that a foaming moldedarticle is obtained (ref: Patent Document 1).

CITATION LIST Patent Document

Patent Document 1: U.S. Unexamined Patent Application Publication No.2012/0329892

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

In the thermoplastic polyurethane resin of the above-described PatentDocument 1, mechanical properties such as tear strength areinsufficient, and further improvement of the mechanical properties arerequired.

An object of the present invention is to provide a foaming thermoplasticpolyurethane resin having excellent mechanical properties.

Means for Solving the Problem

The present invention [1] includes a foaming thermoplastic polyurethaneresin being a reaction product of a polyisocyanate component containinga bis(isocyanatomethyl)cyclohexane and a polyol component, wherein in apeak of chromatogram obtained by measurement of the foamingthermoplastic polyurethane resin with gel permeation chromatography, thearea of a high molecular weight component having a weight averagemolecular weight of 400,000 or more with respect to the total area ofthe peak is 25% or more and 60% or less.

The present invention [2] includes the foaming thermoplasticpolyurethane resin described in the above-described [1], wherein anaggregation temperature of the foaming thermoplastic polyurethane resinmeasured with a differential scanning calorimeter is 90° C. or more and180° C. or less.

The present invention [3] includes the foaming thermoplasticpolyurethane resin described in the above-described [1] or [2], whereinthe bis(isocyanatomethyl)cyclohexane is a1,4-bis(isocyanatomethyl)cyclohexane.

The present invention [4] includes the foaming thermoplasticpolyurethane resin described in the above-described [3], wherein the1,4-bis(isocyanatomethyl)cyclohexane contains a trans-isomer at a ratioof 70 mol % or more and 96 mol % or less.

The present invention [5] includes a method for producing a foamingthermoplastic polyurethane resin including a reaction step of obtaininga primary product by allowing a polyisocyanate component containing abis(isocyanatomethyl)cyclohexane to react with a polyol component and aheat treatment step of heat treating the primary product at 50° C. ormore and 100° C. or less for 3 days or more and 10 days or less.

The present invention [6] includes a molded article containing thefoaming thermoplastic polyurethane resin described in any one of theabove-described [1] to [4].

The present invention [7] includes the molded article described in theabove-described [6] being a midsole.

The present invention [8] includes the molded article described in theabove-described [7] being a shock absorber.

The present invention [9] includes the molded article described in theabove-described [6] being a chemical mechanical polishing pad.

The present invention [10] includes the molded article described in theabove-described [6] being an automobile interior member.

Effect of the Invention

The foaming thermoplastic polyurethane resin of the present inventioncontains a high molecular weight component having a weight averagemolecular weight in a specific range at a specific ratio. Thus, breakingof foam at the time of foaming can be reduced, and a uniform minute cellcan be obtained. As a result, excellent mechanical properties can beachieved.

According to the method for producing a foaming thermoplasticpolyurethane resin of the present invention, the heat treatment step ofa relatively long period of time is included, so that the foamingthermoplastic polyurethane resin can contain the high molecular weightcomponent at a specific ratio. Thus, the foaming thermoplasticpolyurethane resin having excellent mechanical properties can beobtained.

The molded article of the present invention is molded from the foamingthermoplastic polyurethane resin of the present invention, so thatexcellent mechanical properties can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows chromatogram at the time of measurement of a foamingthermoplastic polyurethane resin of Example 2 and Comparative Example 1with gel permeation chromatography.

DESCRIPTION OF EMBODIMENTS

A foaming thermoplastic polyurethane resin (i.e. a thermoplasticpolyurethane resin for foaming) of the present invention is obtained byallowing a polyisocyanate component to react with a polyol component.

That is, the foaming thermoplastic polyurethane resin of the presentinvention is a reaction product of the polyisocyanate component with thepolyol component.

In the present invention, the polyisocyanate component contains abis(isocyanatomethyl)cyclohexane as an essential component.

Examples of the bis(isocyanatomethyl)cyclohexane include1,3-bis(isocyanatomethyl)cyclohexane and1,4-bis(isocyanatomethyl)cyclohexane. Preferably, in view of symmetricalstructure and improvement of rigidity of the foaming thermoplasticpolyurethane resin, a 1,4-bis(isocyanatomethyl)cyclohexane is used.

The 1,4-bis(isocyanatomethyl)cyclohexane includes a stereoisomer ofcis-1,4-bis(isocyanatomethyl)cyclohexane (hereinafter, referred to as acis-1,4 isomer) and trans-1,4-bis(isocyanatomethyl)cyclohexane(hereinafter, referred to as a trans-1,4 isomer). In the presentinvention, the 1,4-bis(isocyanatomethyl)cyclohexane contains thetrans-1,4 isomer at a ratio of, for example, 60 mol % or more,preferably 70 mol % or more, more preferably 80 mol % or more, furthermore preferably 85 mol % or more, and for example, 99 mol % or less,preferably 96 mol % or less, more preferably 90 mol % or less. In otherwords, in the 1,4-bis(isocyanatomethyl)cyclohexane, the total amount ofthe trans-1,4 isomer and the cis-1,4 isomer is 100 mol %, so that thecis-1,4 isomer is contained at a ratio of, for example, 1 mol % or more,preferably 4 mol % or more, more preferably 10 mol % or more, and forexample, 40 mol % or less, preferably 30 mol % or less, more preferably20 mol % or less, further more preferably 15 mol % or less.

When the content ratio of the trans-1,4 isomer is the above-describedlower limit or more, the mechanical properties of a polyurethane foamingmolded article to be obtained (described later) can be improved. Whenthe content ratio of the trans-1,4 isomer is the above-described upperlimit or less, the hardness, the breaking strength, and the tearstrength of the polyurethane foaming molded article to be obtained(described later) can be improved.

The bis(isocyanatomethyl)cyclohexane can be produced from, for example,a commercially available bis(aminomethyl)cyclohexane and abis(aminomethyl)cyclohexane obtained by a method described in JapaneseUnexamined Patent Publication No. 2011-6382 by, for example, a heat andcold two-step phosgenation method (direct method) and a salificationmethod described in Japanese Unexamined Patent Publication No. H7-309827and Japanese Unexamined Patent Publication No. 2014-55229, and anon-phosgenation method described in Japanese Unexamined PatentPublication No. 2004-244349 and Japanese Unexamined Patent PublicationNo. 2003-212835.

The bis(isocyanatomethyl)cyclohexane can be also prepared as a modifiedproduct as long as the excellent effect of the present invention is notdamaged.

Examples of the modified product of the bis(isocyanatomethyl)cyclohexaneinclude multimers of the bis(isocyanatomethyl)cyclohexane (dimer (forexample, uretodione modified product or the like), trimer (for example,isocyanurate modified product, iminooxadiazinedione modified product, orthe like), or the like); biuret modified products (for example, biuretmodified product or the like produced by reaction of thebis(isocyanatomethyl)cyclohexane with water); allophanate modifiedproducts (for example, allophanate modified product or the like producedby reaction of the bis(isocyanatomethyl)cyclohexane with a monohydricalcohol or a dihydric alcohol); polyol modified products (for example,polyol modified product (adduct) or the like produced by reaction of thebis(isocyanatomethyl)cyclohexane with a trihydric alcohol); oxadiazinetrione modified products (for example, oxadiazine trione or the likeproduced by reaction of the bis(isocyanatomethyl)cyclohexane with acarbonic acid gas); and carbodiimide modified products (for example,carbodiimide modified product or the like produced by decarboxylationcondensation reaction of the bis(isocyanatomethyl)cyclohexane).

The polyisocyanate component can also contain another polyisocyanatesuch as an aliphatic polyisocyanate, an aromatic polyisocyanate, and anaraliphatic polyisocyanate as an optional component as long as theexcellent effect of the present invention is not damaged.

Examples of the aliphatic polyisocyanate include ethylene diisocyanate,trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylenediisocyanate (PDI), hexamethylene diisocyanate (HDI), octamethylenediisocyanate, nonamethylene diisocyanate, 2,2′-dimethylpentanediisocyanate, 2,2,4-trimethylhexane diisocyanate, decamethylenediisocyanate, butene diisocyanate, 1,3-butadiene-1,4-diisocyanate,2,4,4-trimethylhexamethylene diisocyanate, 1,6,11-undecamethylenetriisocyanate, 1,3,6-hexamethylene triisocyanate,1,8-diisocyanate-4-isocyanatomethyl octane,2,5,7-trimethyl-1,8-diisocyanate-5-isocyanatomethyl octane,bis(isocyanatoethyl)carbonate, bis(isocyanatoethyl)ether, 1,4-butyleneglycol dipropylether-ω,ω′-diisocyanate, lysine isocyanatomethyl ester,lysine triisocyanate, 2-isocyanatoethyl-2,6-diisocyanate hexanoate,2-isocyanatopropyl-2,6-diisocyanate hexanoate,bis(4-isocyanate-n-butylidene)pentaerythritol, and2,6-diisocyanatemethylcaproate.

An example of the aliphatic polyisocyanate includes an alicyclicpolyisocyanate (excluding bis(isocyanatomethyl)cyclohexane).

Examples of the alicyclic polyisocyanate (excluding thebis(isocyanatomethyl)cyclohexane) include isophorone diisocyanate(IPDI), trans-trans-, trans-cis-, and cis-cis-dicyclohexylmethanediisocyanate and a mixture thereof (hydrogenated MDI), 1.3- or1,4-cyclohexane diisocyanate and a mixture thereof, 1.3- or1,4-bis(isocyanatoethyl)cyclohexane, methylcyclohexane diisocyanate,2,2′-dimethyldicyclohexylmethane diisocyanate, dimer acid diisocyanate,2,5-diisocyanatomethylbicyclo[2,2,1]-heptane,2,6-diisocyanatomethylbicyclo[22,21]-heptane (NBDI) that is an isomerthereof.2-isocyanatomethyl-2-(3-isocyanatopropyl)-5-isocyanatomethylbicyclo-[2,2,1]-heptane,2-isocyanatomethyl-2-(3-isocyanatopropyl)-6-isocyanatomethylbicyclo-[2,2,1]-heptane,2-isocyanatomethyl-3-(3-isocyanatopropyl)-5-(2-isocyanatoethyl)-bicyclo-[2,2,I]-heptane.2-isocyanatomethyl-3-(3-isocyanatopropyl)-6-(2-isocyanatoethyl)-bicyclo-[2,2,1]-heptane,2-isocyanatomethyl-2-(3-isocyanatopropyl)-5-(2-isocyanatoethyl)-bicyclo-[2,2,1]-heptane,and2-isocyanatomethyl-2-(3-isocyanatopropyl)-6-(2-isocyanatoethyl)-bicyclo-[2,2,1]-heptane.

Examples of the aromatic polyisocyanate include 2,4-tolylenediisocyanate, 2,6-tolylene diisocyanate, and an isomer mixture of thetolylene diisocyanate (TDI); 4,4′-diphenylmethane diisocyanate,2,4′-diphenylmethane diisocyanate, 2,2′-diphenylmethane diisocyanate,and an optional isomer mixture of the diphenylmethane diisocyanate(MDI); toluidine diisocyanate (TODI); paraphenylene diisocyanate; andnaphthalene diisocyanate (NDI)

Examples of the araliphatic polyisocyanate include 1,3- or 1,4-xylylenediisocyanate and a mixture thereof (XDI), and 1,3- or1,4-tetramethylxylylene diisocyanate and a mixture thereof (TMXDI).

These other polyisocyanates can be used alone or in combination of twoor more.

The other polyisocyanate can be also prepared as a modified product aslong as the excellent effect of the present invention is not damaged.

Examples of the modified product of the other polyisocyanate includemultimers (dimer, trimer, or the like), biuret modified products,allophanate modified products, polyol modified products,oxadiazinetrione modified products, and carbodiimide modified productsof the other polyisocyanate.

The content ratio of the other polyisocyanate with respect to the totalamount of the polyisocyanate component is, for example, 50 mass % orless, preferably 30 mass % or less, more preferably 20 mass % or less.

The polyisocyanate component can contain a monoisocyanate as an optionalcomponent as long as the excellent effect of the present invention isnot damaged.

Examples of the monoisocyanate include methyl isocyanate, ethylisocyanate, n-hexyl isocyanate, cyclohexyl isocyanate, 2-ethylhexylisocyanate, phenyl isocyanate, and benzyl isocyanate.

The content ratio of the monoisocyanate with respect to the total amountof the polyisocyanate component is, for example, 20 mass % or less,preferably 10 mass % or less.

As the polyisocyanate component, preferably, abis(isocyanatomethyl)cyclohexane is used alone.

In the present invention, as the polyol component, a component having amolecular weight of 60 or more and 5000 or less and containing acompound having two or more hydroxyl groups in a molecule (hereinafter,referred to as a hydroxyl group-containing compound) is usually used. Asthe polyol component, preferably, a first polyol component having amolecular weight of 400 or more and 5000 or less, and a second polyolcomponent having a molecular weight of 60 or more and below 400 are usedin combination.

When a polymer is contained in the polyol component, as the molecularweight of the polymer, a number average molecular weight is used. Insuch a case, the number average molecular weight can be determined withmeasurement by a GPC method, and a hydroxyl value and formulation ofeach of the components polymerizing the polymer (hereinafter, the same).

As the first polyol component, for example, a compound having amolecular weight within the above-described range and having two or morehydroxyl groups in a molecule is used, and preferably, a polymer havinga number average molecular weight within the above-described range andhaving two or more hydroxyl groups in a molecule is used.

To be specific, examples of the first polyol component include polyetherpolyol, polyester polyol, polycarbonate polyol, vegetable oil polyol,polyolefin polyol, and acrylic polyol.

Examples of the polyether polyol include polyoxyalkylene polyol andpolytetramethylene ether polyol.

The polyoxyalkylene polyol is an addition polymer of an alkylene oxidewith a low molecular weight polyol, a low molecular weight polyamine, orthe like as an initiator.

An example of the low molecular weight polyol includes the second polyolto be described later.

Examples of the alkylene oxide include propylene oxide, ethylene oxide,and butylene oxide. These alkylene oxides can be used alone or incombination of two or more. Among these, preferably, a propylene oxideand an ethylene oxide are used. An example of the polyoxyalkylene polyolincludes a polyethylene glycol, a polypropylene glycol, and a randomand/or block copolymer of a propylene oxide and an ethylene oxide.

An example of the polytetramethylene ether polyol includes aring-opening polymer (polytetramethylene ether glycol) obtained bycationic polymerization of tetrahydrofuran and an amorphous(noncrystalline) polytetramethylene ether glycol that copolymerizes analkyl-substituted tetrahydrofuran or a dihydric alcohol (describedlater) with a polymerization unit of tetrahydrofuran.

The amorphous (noncrystalline) is defined as a state of being liquid ata normal temperature (25° C.) (hereinafter, the same).

An example of the polyester polyol includes a polycondensate obtained byallowing the above-described low molecular weight polyol to react with apolybasic acid under known conditions.

Examples of the polybasic acid include saturated aliphatic dicarboxylicacids such as oxalic acid, malonic acid, succinic acid, methylsuccinicacid, glutaric acid, adipic acid, 1,1-dimethyl-1,3-dicarboxypropane,3-methyl-3-ethylglutaric acid, azelaic acid, sebacic acid, and othersaturated aliphatic dicarboxylic acids (carbon number of 11 to 13);unsaturated aliphatic dicarboxylic acids such as maleic acid, fumaricacid, itaconic acid, and others; aromatic dicarboxylic acids such asorthophthalic acid, isophthalic acid, terephthalic acid, toluenedicarboxylic acid, naphthalene dicarboxylic acid, and others; alicyclicdicarboxylic acids such as hexahydrophthalic acid and others; othercarboxylic acids such as dimer acid, hydrogenated dimer acid, HET acid,and others; anhydrides derived from the carboxylic acids such as oxalicanhydrides, succinic anhydrides, maleic anhydrides, phthalic anhydrides,2-alkyl (C12 to C18) succinic anhydrides, tetrahydrophthalic anhydrides,and trimellitic anhydrides; and furthermore, acid halides derived fromthe carboxylic acids such as oxalyl dichlorides, adipic aciddichlorides, and sebacic acid dichlorides.

An example of the polyester polyol includes a polyester polyol derivedfrom plants, to be specific, a plant oil-based polyester polyol obtainedby subjecting a hydroxy carboxylic acid such as hydroxylgroup-containing vegetable oil fatty acid (for example, castor oil fattyacid containing a ricinoleic acid, hydrogenated castor oil fatty acidcontaining a 12-hydroxystearic acid, or the like) to condensationreaction under known conditions with the above-described low molecularweight polyol as an initiator.

Examples of the polyester polyol include a lactone-based polyesterpolyol including a polycaprolactone polyol and a polyvalerolactonepolyol obtained by subjecting lactones such as ε-caprolactone andγ-valerolactone and lactides such as L-lactide and D-lactide toring-opening polymerization with the above-described low molecularweight polyol (preferably, dihydric alcohol (described later)) as theinitiator, and furthermore, a copolymer of these with the dihydricalcohol (described later).

Examples of the polycarbonate polyol include a ring-opening polymer ofethylene carbonate with the above-described low molecular weight polyol(preferably, dihydric alcohol (described later)) as an initiator and anamorphous polycarbonate polyol obtained by copolymerizing the dihydricalcohols (described later) such as 1,4-butanediol, 1,5-pentanediol,3-methyl-1,5-pentanediol, and 1,6-hexanediol with the ring-openingpolymer.

Examples of the vegetable oil polyol include hydroxyl group-containingvegetable oils such as castor oil and coconut oil. Also, examplesthereof include a castor oil polyol and an ester-modified castor oilpolyol obtained by allowing a castor oil fatty acid to react with apolypropylene polyol.

Examples of the polyolefin polyol include a polybutadiene polyol and apartially saponified ethylene-vinyl acetate copolymer.

An example of the acrylic polyol includes a copolymer obtained bycopolymerizing a hydroxyl group-containing acrylate with acopolymerizable vinyl monomer that is copolymerizable with the hydroxylgroup-containing acrylate.

Examples of the hydroxyl group-containing acrylate include2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate,hydroxybutyl (meth)acrylate, 2,2-dihydroxymethylbutyl (meth)acrylate,polyhydroxyalkyl maleate, and polyhydroxyalkyl fumarate. Preferably, a2-hydroxyethyl (meth)acrylate is used.

Examples of the copolymerizable vinyl monomer include alkyl(meth)acrylates (carbon number of 1 to 12) such as methyl(meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl(meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl(meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl(meth)acrylate, hexyl (meth)acrylate, isononyl (meth)acrylate,2-ethylhexyl (meth)acrylate, and cyclohexyl acrylate; aromatic vinylssuch as styrene, vinyltoluene, and α-methylstyrene; vinyl cyanides suchas (meth)acrylonitrile; vinyl monomers containing a carboxyl group suchas (meth)acrylic acid, fumaric acid, maleic acid, and itaconic acid oralkyl esters thereof; alkanepolyol poly(meth)acrylates such asethyleneglycol di(meth)acrylate, butyleneglycol di(meth)acrylate,hexanediol di(meth)acrylate, and oligoethyleneglycol di(meth)acrylate;and vinyl monomers containing an isocyanate group such as3-(2-isocyanate-2-propyl)-α-methylstyrene.

The acrylic polyol can be obtained by copolymerizing the hydroxylgroup-containing acrylate with the copolymerizable vinyl monomer underthe presence of an appropriate solvent and a polymerization initiator.

Examples of the acrylic polyol include a silicone polyol and a fluorinepolyol.

An example of the silicone polyol includes an acrylic polyol in which asilicone compound containing a vinyl group such asγ-methacryloxypropyltrimethoxysilane is blended as a copolymerizablevinyl monomer in the copolymerization of the above-described acrylicpolyol.

An example of the fluorine polyol includes an acrylic polyol in which afluorine compound containing a vinyl group such as tetrafluoroethyleneand chlorotrifluoroethylene is blended as a copolymerizable vinylmonomer in the copolymerization of the above-described acrylic polyol.

These first polyol components can be used alone or in combination of twoor more.

As the first polyol component, preferably, a polyether polyol and apolyester polyol are used, more preferably, a polyethylene glycol, apolytetramethylene ether glycol, and a polycaprolactone polyol are used,further more preferably, a polycaprolactone polyol is used.

When the first polyol component is the above-described polyol, apolyurethane foaming molded article (described later) having excellentmechanical properties such as breaking strength and tear strength can beobtained.

The number average molecular weight of the first polyol component is,for example, 400 or more, preferably 500 or more, more preferably 1000or more, further more preferably 2000 or more, and for example, 5000 orless, preferably 4000 or less, more preferably 3000 or less.

When the molecular weight of the first polyol component is within theabove-described range, excellent mechanical properties can be developedeven in the case of an increase in an expansion ratio.

An example of the second polyol component includes a compound (monomer)having two or more hydroxyl groups in a molecule and having a molecularweight of 60 or more and below 400.

To be specific, examples of the second polyol component includepolyhydric alcohols including dihydric alcohols such as ethylene glycol,1,3-propylene glycol, 1,2-propylene glycol, 1,4-buthylene glycol(1,4-butane diol, 1,4-BD), 1,3-butylene glycol, 1,2-butylene glycol,1,5-pentanediol, 1,6-hexanediol, neopentyl glycol,3-methyl-1,5-pentanediol, 2,2,2-trimethylpentanediol,3,3-dimethylolheptane, alkane (C7 to C11) diol, cyclohexanedimethanol(1,3- or 1,4-cyclohexanedimethanol and a mixture thereof),cyclohexanediol (1,3- or 1,4-cyclohexanediol and a mixture thereof),1,4-dihydroxy-2-butene, 2,6-dimethyl-1-octene-3,8-diol, diethyleneglycol, triethylene glycol, dipropylene glycol, 1,2-benzenediol (alsoknown as catechol), 1,3-benzenediol, 1,4-benzenediol, bisphenol A andhydrogenated product thereof; trihydric alcohols such as glycerin,trimethylol propane, and triisopropanolamine; and tetrahydric alcoholssuch as tetramethylolmethane (pentaerythritol) and diglycerin.

These second polyol components can be used alone or in combination oftwo or more.

As the second polyol component, preferably, a dihydric alcohol is used,more preferably, a 1,4-butanediol is used.

When the second polyol component is the above-described polyol, apolyurethane foaming molded article (described later) having excellentmechanical properties such as breaking strength can be obtained.

The number average molecular weight of the second polyol component is,for example, 60 or more, preferably 80 or more, and for example, below400, preferably, below 300.

When the molecular weight of the second polyol component is within theabove-described range, the expansion ratio can be increased, and a lightpolyurethane foaming molded article (described later) can be obtained.

In the polyol component, as the content ratio of the first polyolcomponent and the second polyol component, the ratio of the first polyolcomponent with respect to the total amount of the first polyol componentand the second polyol component is, for example, 5 mol % or more,preferably 7 mol % or more, more preferably 10 mol % or more, furthermore preferably 20 mol % or more, and for example, 75 mol %/o or less,preferably 65 mol % or less, more preferably 50 mol % or less. The ratioof the second polyol component with respect to the total amount of thefirst polyol component and the second polyol component is, for example,25 mol % or more, preferably 35 mol % or more, more preferably 50 mol %or more, and for example, 95 mol % or less, preferably 93 mol % or less,more preferably 90 mol % or less, further more preferably 80 mol % orless.

When the content ratio of the first polyol component and the secondpolyol component is within the above-described range, the mechanicalproperties of the polyurethane foaming molded article to be obtained(described later) can be improved.

The foaming thermoplastic polyurethane resin of the present inventioncan be obtained by a producing method including a reaction step and aheat treatment step.

The reaction step is a step of obtaining a primary product (reactionproduct before heat treatment) by allowing the above-describedpolyisocyanate component to react with the above-described polyolcomponent.

To react each of the components described above (polyisocyanatecomponent, polyol component), for example, a known method such as oneshot method and prepolymer method is used. Preferably, a prepolymermethod is used.

When each of the components described above reacts by the prepolymermethod, a polyurethane foaming molded article (described later) havingexcellent mechanical properties can be obtained.

To be specific, in the prepolymer method, first, the polyisocyanatecomponent reacts with the first polyol component, so that an isocyanategroup-terminated polyurethane prepolymer is synthesized (prepolymersynthesis step).

In the prepolymer synthesis step, the polyisocyanate component reactswith the first polyol component by, for example, a polymerization methodsuch as bulk polymerization and solution polymerization.

In the bulk polymerization, for example, under a nitrogen gas stream,the polyisocyanate component reacts with the first polyol component at areaction temperature of, for example, 50° C. or more, and for example,250° C. or less, preferably 200° C. or less for, for example, 0.5 hoursor more, and for example, 15 hours or less.

In the solution polymerization, the polyisocyanate component and thefirst polyol component are added to an organic solvent to react at areaction temperature of, for example, 50° C. or more, and for example,120° C. or less, preferably 100° C. or less for, for example, 0.5 hoursor more, and for example, 15 hours or less.

Examples of the organic solvent include ketones such as acetone, methylethyl ketone, methyl isobutyl ketone, and cyclohexanone; nitriles suchas acetonitrile; alkyl esters such as methyl acetate, ethyl acetate,butyl acetate, and isobutyl acetate; aliphatic hydrocarbons such asn-hexane, n-heptane, and octane; alicyclic hydrocarbons such ascyclohexane and methyl cyclohexane; aromatic hydrocarbons such astoluene, xylene, and ethyl benzene; glycol ether esters such as methylcellosolve acetate, ethyl cellosolve acetate, methyl carbitol acetate,ethyl carbitol acetate, ethylene glycol ethyl ether acetate, propyleneglycol methyl ether acetate, 3-methyl-3-methoxybutylacetate, andethyl-3-ethoxypropionate; ethers such as diethyl ether, tetrahydrofuran,and dioxane; halogenated aliphatic hydrocarbons such as methyl chloride,methylene chloride, chloroform, carbon tetrachloride, methyl bromide,methylene iodide, and dichloroethane; and aprotic polar solvents such asN-methyl pyrrolidone, dimethyl formamide, N,N′-dimethylacetamide,dimethyl sulfoxide, and hexamethylphosphonylamide.

Furthermore, in the above-described polymerization reaction, forexample, a known urethane-formation catalyst such as amines and organicmetal compound can be added as needed.

Examples of the amines include tertiary amines such as triethylamine,triethylenediamine, bis-(2-dimethylaminoethyl) ether, andN-methylmorpholine; quaternary ammonium salts such astetraethylhydroxylammonium; and imidazoles such as imidazole and2-ethyl-4-methylimidazole.

Examples of the organic metal compound include organic tin compoundssuch as tin acetate, tin octylate, tin oleate, tin laurate, dibutyltindiacetate, dimethyltin dilaurate, dibutyltin dilaurate, dibutyltindimercaptide, dibutyltin maleate, dibutyltin dilaurate, dibutyltindineodecanoate, dioctyltin dimercaptide, dioctyltin dilaurate, anddibutyltin dichloride; organic lead compounds such as lead octanoate andlead naphthenate; organic nickel compounds such as nickel naphthenate;organic cobalt compounds such as cobalt naphthenate; organic coppercompounds such as copper octenoate; and organic bismuth compounds suchas bismuth octanoate (bismuth octylate) and bismuth neodecanoate, andpreferably, a tin octylate and a bismuth octylate are used.

Furthermore, examples of the urethane-formation catalyst includepotassium salts such as potassium carbonate, potassium acetate, andpotassium octylate.

These urethane-formation catalysts can be used alone or in combinationof two or more.

The addition ratio of the urethane-formation catalyst with respect to10000 parts by mass of the total amount of the polyisocyanate componentand the first polyol component is, for example, 0.001 parts by mass ormore, preferably 0.01 parts by mass or more, and for example, 1 part bymass or less, preferably 0.5 parts by mass or less.

In the above-described polymerization reaction, an unreactedpolyisocyanate component, a catalyst, and an organic solvent (when thecatalyst and the organic solvent are used) can be removed by, forexample, a known removing method such as distillation and extraction.

In the prepolymer synthesis step, as the mixing ratio of each of thecomponents, the equivalent ratio (isocyanate group/hydroxyl group) ofthe isocyanate group in the polyisocyanate component with respect to thehydroxyl group in the first polyol component is, for example, 2.0 ormore, preferably 2.5 or more, and for example, 20 or less, preferably 15or less, more preferably 10 or less, further more preferably 6.0 orless.

To be more specific, as the mixing ratio of each of the components inthe prepolymer synthesis step, the ratio of the polyisocyanate componentwith respect to 100 parts by mass of the first polyol component is, forexample, 5 parts by mass or more, preferably 10 parts by mass or more,more preferably 15 parts by mass or more, and for example, 100 parts bymass or less, preferably 70 parts by mass or less, more preferably 50parts by mass or less, further more preferably 30 parts by mass or less.

In the method, the above-described components react until the contentratio of the isocyanate group reaches, for example, 1.0 mass % or more,preferably 3.0 mass % or more, more preferably 4.0 mass % or more, andfor example, 30.0 mass % or less, preferably 19.0 mass % or less, morepreferably 16.0 mass % or less, further more preferably 12.0 mass % orless, further more preferably 10.0 mass % or less, particularlypreferably 5.0 mass % or less. In this manner, the isocyanategroup-terminated polyurethane prepolymer can be obtained.

The isocyanate group content (content ratio of the isocyanate group) canbe obtained by a known method such as titration method bydi-n-butylamine and FT-IR analysis.

Next, in this method, the isocyanate group-terminated polyurethaneprepolymer obtained as described above reacts with the second polyolcomponent, so that a primary product of the polyisocyanate component andthe polyol component is obtained (chain extension step).

That is, in this method, the second polyol component is a chainextension agent.

In the chain extension step, the isocyanate group-terminatedpolyurethane prepolymer reacts with the second polyol component by, forexample, a polymerization method such as the above-described bulkpolymerization and the above-described solution polymerization.

The reaction temperature is, for example, a room temperature or more,preferably 50° C. or more, and for example, 200° C. or less, preferably150° C. or less, and the reaction time is, for example, 5 minutes ormore, preferably 1 hour or more, and for example, 72 hours or less,preferably 48 hours or less.

As the mixing ratio of each of the components, the equivalent ratio(isocyanate group/hydroxyl group) of the isocyanate group in theisocyanate group-terminated polyurethane prepolymer with respect to thehydroxyl group in the second polyol component is, for example, 0.75 ormore, preferably 0.9 or more, and for example, 1.3 or less, preferably1.1 or less.

To be more specific, as the mixing ratio of each of the components inthe chain extension step, the ratio of the second polyol component withrespect to 100 parts by mass of the isocyanate group-terminatedpolyurethane prepolymer is, for example, 1.0 part by mass or more,preferably 2.0 parts by mass or more, more preferably 3.0 parts by massor more, and for example, 30 parts by mass or less, preferably 20 partsby mass or less, more preferably 15 parts by mass or less, further morepreferably 10 parts by mass or less, particularly preferably 6.0 partsby mass or less.

In the chain extension step, to adjust the hard segment concentration(described later) of the foaming thermoplastic polyurethane resin to beobtained, the first polyol component can be also blended in addition tothe second polyol component.

In the chain extension step, when the first polyol component is blended,the mixing ratio thereof with respect to 100 parts by mass of theisocyanate group-terminated polyurethane prepolymer is, for example, 5parts by mass or more, preferably 10 parts by mass or more, morepreferably 50 parts by mass or more, and for example, 120 parts by massor less, preferably 10 parts by mass or less, and the mixing ratiothereof with respect to 1 part by mass of the second polyol componentis, for example, 10 parts by mass or more, preferably 20 parts by massor more, and for example, 100 parts by mass or less, preferably 50 partsby mass or less, more preferably 30 parts by mass or less.

Furthermore, in the reaction, the above-described urethane-formationcatalyst can be added as needed. The urethane-formation catalyst can beblended in the isocyanate group-terminated polyurethane prepolymerand/or the second polyol component, and also can be separately blendedat the time of mixture of these.

As the method for obtaining the above-described primary product, whenthe one shot method is used, the polyisocyanate component and the polyolcomponent (including the first polyol component and the second polyolcomponent) are simultaneously blended to be stirred and mixed at such aratio that the equivalent ratio (isocyanate group/hydroxyl group) of theisocyanate group in the polyisocyanate component with respect to thehydroxyl group in the polyol component is, for example, 0.9 or more,preferably 0.95 or more, more preferably 0.98 or more, and for example,1.2 or less, preferably 1.1 or less, more preferably 1.08 or less.

The stirring and mixing is, for example, performed under an inert gas(for example, nitrogen) atmosphere at a reaction temperature of, forexample, 40° C. or more, preferably 100° C. or more, and for example,280° C. or less, preferably 260° C. or less and a reaction time of, forexample, 30 seconds or more and 1 hour or less.

The method for the stirring and mixing is not particularly limited, anda method for the stirring and mixing by using a known mixing device suchas mixing tank equipped with a disper, a dissolver, and a turbine blade,circulation-type low pressure or high pressure impingement mixingdevice, high-speed stirring mixer, static mixer, kneader, uniaxial orbiaxial rotation extruder, and belt conveyor is used.

At the time of the stirring and mixing, the above-describedurethane-formation catalyst and the above-described organic solvent canbe added at an appropriate ratio as needed.

The heat treatment step is a step of obtaining a secondary product(reaction product after the heat treatment, that is, the foamingthermoplastic polyurethane resin that is a reaction product) bysubjecting the above-described primary product to heat treatment.

In the heat treatment step, the primary product obtained in theabove-described reaction step is subjected to heat treatment by beingleft to stand for a predetermined heat treatment period at apredetermined heat treatment temperature to be thereafter dried at 50°C. or more and 100° C. or less for 6 hours or more and 3 days or less.

The heat treatment temperature is, for example, 50° C. or more,preferably 60° C. or more, more preferably 70° C. or more, and forexample, 100° C. or less, preferably 90° C. or less.

When the heat treatment temperature is the above-described lower limitor more, a high molecular weight component can be efficiently containedat a predetermined ratio, and when the heat treatment temperature is theabove-described upper limit or less, the resistance to discoloration byultraviolet light (UV) of the polyurethane foaming molded article to beobtained (described later) can be improved.

The heat treatment period is, for example, 3 days or more, preferably 4days or more, more preferably 5 days or more, further more preferably 6days or more, and for example, 10 days or less, preferably 9 days orless, more preferably 8 days or less.

When the heat treatment period is the above-described lower limit ormore, a high molecular weight component can be contained in the foamingthermoplastic polyurethane resin to be obtained at a predeterminedamount or more, so that the mechanical properties of the polyurethanefoaming molded article to be obtained (described later) can be improved,and when the heat treatment period is the above-described upper limit orless, the high molecular weight component content in the foamingthermoplastic polyurethane resin to be obtained can be suppressed at apredetermined amount or less, so that the mechanical properties and theresistance to discoloration by ultraviolet light (UV) of thepolyurethane foaming molded article to be obtained (described later) canbe improved.

In this manner, the foaming thermoplastic polyurethane resin can beobtained.

Also, a known additive can be added to the foaming thermoplasticpolyurethane resin as needed. Examples thereof include antioxidants,heat resistant stabilizers, ultraviolet absorbers, light resistantstabilizers, furthermore, plasticizers, blocking inhibitors, releaseagents, pigments, dyes, lubricants, fillers, hydrolysis inhibitors,corrosion inhibitors, fillers, and bluing agents. These additives may beadded at the time of the mixture, at the time of the synthesis, or afterthe synthesis of each of the components.

The heat resistant stabilizer is not particularly limited, and a knownheat resistant stabilizer (for example, described in a catalog of BASFJapan) is used. To be more specific, examples thereof includephosphorus-based treatment heat stabilizer, lactone-based treatment heatstabilizer, and sulfur-based treatment heat stabilizer.

The ultraviolet absorber is not particularly limited, and a knownultraviolet absorber (for example, described in a catalog of BASF Japan)is used. To be more specific, examples thereof include benzotriazoleultraviolet absorber, triazine ultraviolet absorber, and benzophenoneultraviolet absorber.

The light resistant stabilizer is not particularly limited, and a knownlight resistant stabilizer (for example, described in a catalog of ADEKACORPORATION) is used. To be more specific, examples thereof includebenzoate light stabilizer and hindered amine light stabilizer.

Each of these additives is added with respect to the foamingthermoplastic polyurethane resin at a ratio of, for example, 0.01 mass %or more, preferably 0.1 mass % or more, and for example, 3.0 mass % orless, preferably 2.0 mass % or less.

The foaming thermoplastic polyurethane resin of the present inventionobtained by the producing method contains the high molecular weightcomponent (component having a weight average molecular weight of 400,000or more, preferably 500,000 or more) at a specific ratio. Thus, themechanical properties of the polyurethane foaming molded article to beobtained (described later) can be improved.

To be specific, the content ratio of the high molecular weight componentof the foaming thermoplastic polyurethane resin corresponds to the areaof the high molecular weight component having a weight average molecularweight of 400,000 or more with respect to the total area of the peak inthe peak of the chromatogram obtained by measurement of the foamingthermoplastic polyurethane resin with gel permeation chromatography, andis, for example, 25% or more, preferably 30% or more, more preferably36% or more, further more preferably 40% or more, particularlypreferably 44% or more, and 60% or less, preferably 55% or less, morepreferably 50% or less, further more preferably 46% or less,particularly preferably 45% or less. The peak of the chromatogram is amolecular weight distribution curve derived from the foamingthermoplastic polyurethane resin, and the peak derived from impuritiessuch as solvent is removed.

In the present invention, the content ratio of the high molecular weightcomponent of the foaming thermoplastic polyurethane resin can bemeasured with gel permeation chromatography equipped with a differentialrefractometer (GPC measurement) under the specific conditions (ref:Examples to be described later).

To be specific, in the present invention, the obtained foamingthermoplastic polyurethane resin is, for example, immersed inN-methylpyrrolidone to be stirred and dissolved at, for example, 80° C.or more and 120° C. or less (preferably, about 100° C.) for, forexample, 2 hours or more and 8 hours or less, and the obtained solutionis cooled until a room temperature (25° C.) to be then filtrated,thereby preparing a sample solution. Then, the sample solution issubjected to GPC measurement in accordance with the conditions ofExamples to be described later by using gel permeation chromatographyequipped with the differential refractometer.

When the high molecular weight component of the foaming thermoplasticpolyurethane resin is the above-described lower limit or more, theelongational viscosity can be increased, and breaking of foam at thetime of foaming can be reduced, so that uniformity of a minute cell canbe retained. As a result, the mechanical properties of the polyurethanefoaming molded article to be obtained (described later) can be improved.

When the high molecular weight component of the foaming thermoplasticpolyurethane resin is the above-described upper limit or less, anextreme increase of the elongational viscosity can be suppressed, sothat foaming can be easily controlled. As a result, the deterioration ofthe polyurethane foaming molded article to be obtained (described later)based on heat and shearing can be suppressed, and the resistance todiscoloration by ultraviolet light (UV) can be improved.

The hard segment concentration of the foaming thermoplastic polyurethaneresin is, for example, 3 mass % or more, preferably 5 mass % or more,more preferably 8 mass % or more, and for example, 55 mass % or less,preferably 50 mass % or less, more preferably 45 mass % or less, furthermore preferably 35 mass % or less, particularly preferably 20 mass % orless.

When the hard segment concentration of the foaming thermoplasticpolyurethane resin is within the above-described range, the uniformityof the cell that constitutes the polyurethane foaming molded article tobe obtained (described later) can be improved.

The hard segment (hard segment formed by reaction of the polyisocyanatecomponent with the second polyol component) concentration of the foamingthermoplastic polyurethane resin can be, for example, calculated fromthe mixing ratio (charging) of each of the components (ref: Examples tobe described later).

The aggregation temperature of the foaming thermoplastic polyurethaneresin corresponds to that of the hard segment phase in the foamingthermoplastic polyurethane resin, and is, for example, 75° C. or more,preferably 90° C. or more, more preferably 100° C. or more, further morepreferably 110° C. or more, particularly preferably 130° C. or more, andfor example, 200° C. or less, preferably 180° C. or less, morepreferably 170° C. or less, further more preferably 150° C. or less,particularly preferably 140° C. or less.

When the aggregation temperature of the foaming thermoplasticpolyurethane resin is the above-described lower limit or more, thebreaking strength and the tear strength of the polyurethane foamingmolded article to be obtained (described later) can be improved, andwhen the aggregation temperature of the foaming thermoplasticpolyurethane resin is the above-described upper limit or less,improvement of the rebound resilience and suppression of the compressionpermanent set of the polyurethane foaming molded article to be obtained(described later) can be achieved.

The aggregation temperature of the foaming thermoplastic polyurethaneresin can be, for example, measured by differential scanning calorimetry(DSC measurement) in conformity with the conditions of Examples.

The hardness (ASKER A (in conformity with JIS K7311 (1995)), ASKER D (inconformity with JIS K7311 (1995))) of the foaming thermoplasticpolyurethane resin is, for example, 50 A or more, preferably 70 A ormore, more preferably 72 A or more, further more preferably 75 A ormore, particularly preferably 78 A or more, and for example, 60 D orless, preferably 55 D or less, more preferably 50 D or less, furthermore preferably 95 A or less, particularly preferably 90 A or less,especially preferably 85 A or less.

The present invention includes a molded article, to be specific, afoaming molded article including the above-described foamingthermoplastic polyurethane resin of the present invention. The foamingmolded article is molded from the foaming thermoplastic polyurethaneresin.

The foaming molded article can be, for example, obtained by molding theabove-described foaming thermoplastic polyurethane resin by a knownfoaming molding method such as extrusion foaming method, injectionfoaming method, and bead foaming method.

To be specific, in the extrusion foaming method, for example, theabove-described foaming thermoplastic polyurethane resin is melted, anda known foaming agent (for example, supercritical carbon dioxide gas) iskneaded to be then extruded, so that a polyurethane foaming moldedarticle can be obtained.

In the injection foaming method, for example, the above-describedfoaming thermoplastic polyurethane resin is melted, and a known foamingagent (for example, supercritical carbon dioxide gas) is kneaded to bethen injected and molded with a metal mold, so that a polyurethanefoaming molded article can be obtained.

In the bead foaming method, for example, the above-described foamingthermoplastic polyurethane resin is melted, and a known foaming agent(for example, supercritical carbon dioxide gas) is kneaded and then, adischarged foaming body strand is cut into a piece having an appropriatesize, so that a foaming bead is obtained. The obtained foaming bead ismelted and molded with a metal mold, so that a polyurethane foamingmolded article can be obtained.

The uniformity (in conformity with Examples to be described later) ofthe cell in the obtained foaming molded article is, for example, 4 ormore, preferably above 4, and for example, 5 or less.

The core density (in conformity with Examples to be described later) ofthe foaming molded article is, for example, 0.01 g/cm³ or more,preferably 0.05 g/cm³ or more, more preferably 0.10 g/cm³ or more,further more preferably 0.20 g/cm³ or more, and for example, 0.5 g/cm³or less, preferably 0.4 g/cm³ or less, more preferably 0.30 g/cm³ orless.

The hardness (in conformity with Examples to be described later, inconformity with JIS K 7312 (1996)) of the foaming molded article is, forexample, 1 C or more, preferably 10 C or more, more preferably 30 C ormore, further more preferably 35 C or more, and for example, 80 C orless, preferably 70 C or less, more preferably 50 C or less, furthermore preferably 45 C or less, particularly preferably 42 C or less.

The rebound resilience (in conformity with Examples to be describedlater) of the foaming molded article is, for example, 5% or more,preferably 30% or more, more preferably 40% or more, further morepreferably 50% or more, particularly preferably 70% or more, especiallypreferably 73% or more, and for example, 85% or less, preferably 83% orless.

The compression permanent set (in conformity with Examples to bedescribed later) of the foaming molded article is, for example, 0.1% ormore, preferably 1% or more, and for example, 40% or less, preferably25% or less, more preferably 20% or less, further more preferably 13% orless, further more preferably 11% or less, further more preferably 10%or less, particularly preferably 9% or less.

The breaking strength (in conformity with Examples to be describedlater) of the foaming molded article is, for example, 1.0 MPa or more,preferably 1.5 MPa or more, more preferably 1.8 MPa or more, furthermore preferably 2.1 MPa or more, particularly preferably 2.4 MPa ormore, and for example, 5.0 MPa or less, preferably 4.5 MPa or less.

The tear strength (in conformity with Examples to be described later) ofthe foaming molded article is, for example, 2 kN/m or more, preferably 3kN/m or more, more preferably 4 kN/m or more, further more preferably 6kN/m or more, further more preferably 7 kN/m or more, particularlypreferably 10 kN/m or more, and for example, 30 kN/m or less, preferably20 kN/m or less.

The resistance to discoloration by ultraviolet light (UV) of the foamingmolded article (in conformity with Examples to be described later) is,for example, 0.1 or more, preferably 0.3 or more, and for example, 5 orless, preferably 3.5 or less, more preferably 2.5 or less, further morepreferably 2.3 or less, further more preferably 2.0 or less,particularly preferably 1.9 or less.

The molded article of the present invention is molded from the foamingthermoplastic polyurethane resin of the present invention, so that theobtained molded article is the polyurethane foaming molded article andhas excellent mechanical properties.

Thus, the molded article of the present invention can be used in a widevariety of fields including furniture such as mattress and sofa;clothing goods such as brassiere and shoulder pad; medical supplies suchas buffer materials of paper diaper, napkin, and medical tape; sanitarygoods such as cosmetics, facial washing puff, and pillow; shoes articlessuch as sole (outsole and innersole) and midsole; footwear goods(sandals or the like) in various uses such as medical uses; furthermore,body pressure distribution goods such as pad and cushion for vehicles;members touched with a hand such as door trim, instrument panel, andgear knob; heat insulating materials of electric refrigerators andbuildings; shock absorbing materials such as shock absorber; vehiclegoods such as filler, vehicle handle, automobile interior member, andautomobile exterior member; semiconductor production articles such aschemical mechanical polishing (CMP) pad; sports articles such as corematerials of bat and grip; and poles.

Among all, the molded article of the present invention is preferablyused as a midsole, a shock absorber, a chemical mechanical polishing(CMP) pad, sports articles, an automobile interior member, or the likethat require high mechanical properties.

EXAMPLES

Next, the present invention is described based on Production Examples,Synthesis Examples, Examples, and Comparative Examples. The presentinvention is however not limited by these Examples. All designations of“part” or “parts” and “%” mean part or parts by mass and % by mass,respectively, unless otherwise particularly specified in the followingdescription. The specific numerical values in mixing ratio (contentratio), property value, and parameter used in the following descriptioncan be replaced with upper limit values (numerical values defined as “orless” or “below”) or lower limit values (numerical values defined as “ormore” or “above”) of corresponding numerical values in mixing ratio(content ratio), property value, and parameter described in theabove-described “DESCRIPTION OF EMBODIMENTS”.

Production of Bis(isocyanatomethyl)cyclohexane Production Example 1(Production of 1,4-bis(isocyanatomethyl)cyclohexane (1) (Hereinafter,Referred to as 1,4-BIC (1)))

In conformity with the description of Production Example 6 of JapaneseUnexamined Patent Publication No. 2014-55229, a1,4-bis(aminomethyl)cyclohexane having a ratio oftrans-isomer/cis-isomer of 98/2 having a purity of 99.5% or more wasobtained at a yield of 92%.

Thereafter, in conformity with the description of Production Example 1of Japanese Unexamined Patent Publication No. 2014-55229, a heat andcold two-step phosgenation method was performed by using the1,4-bis(aminomethyl)cyclohexane as a material under pressure, so that382 parts by mass of 1,4-BIC (1) was obtained.

The purity of the obtained 1,4-BIC (1) with gas chromatographymeasurement was 99.9%, the color phase with APHA measurement was 5, anda ratio of trans-isomer/cis-isomer with ¹³C-NMR measurement was 98/2.The hydrolysable chlorine concentration (hereinafter, referred to as HCconcentration) was 18 ppm.

Production Example 2 (Production of 1,4-bis(isocyanatomethyl)cyclohexane(2) (Hereinafter, Referred to as 1,4-BIC (2)))

By using a 1,4-bis(aminomethyl)cyclohexane (manufactured by MitsubishiGas Chemical Company, Inc.) having a ratio of trans-isomer/cis-isomer of93/7 with ¹³C-NMR measurement as a material, 385 parts by mass of1,4-BIC (2) was obtained in conformity with the description ofProduction Example 1 of Japanese Unexamined Patent Publication No.2014-55229.

The purity of the obtained 1,4-BIC (2) with gas chromatographymeasurement was 99.9%, the color phase with APHA measurement was 5, anda ratio of trans-isomer/cis-isomer with ¹³C-NMR measurement was 93/7.The HC concentration was 19 ppm.

Production Example 3 (Production of 1,4-bis(isocyanatomethyl)cyclohexane(3) (Hereinafter, Referred to as 1,4-BIC (3)))

A four-neck flask equipped with a stirrer, a thermometer, a reflux tube,and a nitrogen inlet tube was charged with 200 parts by mass of 1,4-BIC(1) obtained in Production Example 1 and 800 parts by mass of 1,4-BIC(2) obtained in Production Example 2 to be then stirred at a roomtemperature for 1 hour under a nitrogen atmosphere, so that 1000 partsby mass of 1,4-BIC (3) was obtained.

The purity of the obtained 1,4-BIC (3) with gas chromatographymeasurement was 99.9%, the color phase with APHA measurement was 5, anda ratio of trans-isomer/cis-isomer with ¹³C-NMR measurement was 94/6.The HC concentration was 19 ppm.

Production Example 4 (Production of 1,4-bis(isocyanatomethyl)cyclohexane(4) (Hereinafter, Referred to as 1,4-BIC (4)))

A four-neck flask equipped with a stirrer, a thermometer, a reflux tube,and a nitrogen inlet tube was charged with 865 parts by mass of 1,4-BIC(2) obtained in Production Example 2 and 135 parts by mass of 1,4-BIC(7) obtained in Production Example 7 to be described later to be thenstirred at a room temperature for 1 hour under a nitrogen atmosphere, sothat 1000 parts by mass of 1,4-BIC (4) was obtained.

The purity of the obtained 1,4-BIC (4) with gas chromatographymeasurement was 99.9%, the color phase with APHA measurement was 5, anda ratio of trans-isomer/cis-isomer with ¹³C-NMR measurement was 86/14.The HC concentration was 19 ppm.

Production Example 5 (Production of 1,4-bis(isocyanatomethyl)cyclohexane(5) (Hereinafter, Referred to as 1,4-BIC (5)))

A four-neck flask equipped with a stirrer, a thermometer, a reflux tube,and a nitrogen inlet tube was charged with 615 parts by mass of 1,4-BIC(2) obtained in Production Example 2 and 385 parts by mass of 1,4-BIC(7) obtained in Production Example 7 to be described later to be thenstirred at a room temperature for 1 hour under a nitrogen atmosphere, sothat 1000 parts by mass of 1,4-BIC (5) was obtained.

The purity of the obtained 1,4-BIC (5) with gas chromatographymeasurement was 99.9%, the color phase with APHA measurement was 5, anda ratio of trans-isomer/cis-isomer with ¹³C-NMR measurement was 73/27.The HC concentration was 21 ppm.

Production Example 6 (Production of 1,4-bis(isocyanatomethyl)cyclohexane(6) (Hereinafter, Referred to as 1,4-BIC (6)))

A four-neck flask equipped with a stirrer, a thermometer, a reflux tube,and a nitrogen inlet tube was charged with 462 parts by mass of 1,4-BIC(2) obtained in Production Example 2 and 538 parts by mass of 1,4-BIC(7) obtained in Production Example 7 to be described later to be thenstirred at a room temperature for 1 hour under a nitrogen atmosphere, sothat 1000 parts by mass of 1,4-BIC (6) was obtained.

The purity of the obtained 1,4-BIC (6) with gas chromatographymeasurement was 99.9%, the color phase with APHA measurement was 5, anda ratio of trans-isomer/cis-isomer with ¹³C-NMR measurement was 65/35.The HC concentration was 20 ppm.

Production Example 7 (Production of 1,4-bis(isocyanatomethyl)cyclohexane(7) (Hereinafter, Referred to as 1,4-BIC (7)))

By using a 1,4-bis(aminomethyl)cyclohexane (manufactured by TokyoChemical Industry Co., Ltd.) having a ratio of trans-isomer/cis-isomerof 41/59 with ¹³C-NMR measurement as a material, 388 parts by mass of1,4-BIC (7) was obtained in conformity with the description ofProduction Example 1 of Japanese Unexamined Patent Publication No.2014-55229.

The purity of the obtained 1,4-BIC (7) with gas chromatographymeasurement was 99.9%, the color phase with APHA measurement was 5, anda ratio of trans-isomer/cis-isomer with ¹³C-NMR measurement was 41/59.The HC concentration was 22 ppm.

Synthesis of Isocyanate Group-Terminated Polyurethane PrepolymerSynthesis Examples 1 to 13

A four-neck flask equipped with a stirrer, a thermometer, a reflux tube,and a nitrogen inlet tube was charged with the polyisocyanate componentand the first polyol component with the type and the mass ratiodescribed in Table 1 to be then stirred at 80° C. for 1 hour under anitrogen atmosphere. Thereafter, in Synthesis Examples 1, 2, 4 to 11,and 13 (isocyanate group-terminated polyurethane prepolymer(hereinafter, referred to as prepolymer) (a), (b), (d) to (k), and (m)),as a catalyst amount, 10 ppm (0.10 parts by mass with respect to 10000parts by mass of the total amount of the polyisocyanate component andthe first polyol component) of tin octylate (trade name: STANOCT,manufactured by API Corporation) diluted in 4 mass % withdiisononyladipate (manufactured by J-PLUS Co., Ltd.) in advance; inSynthesis Example 3 (prepolymer (c)), 10 ppm (0.10 parts by mass withrespect to 10000 parts by mass of the total amount of the polyisocyanatecomponent and the first polyol component) of bismuth octylate (tradename: NEOSTANN U-600, manufactured by NITTO KASEI CO., LTD.) diluted in4 mass % with diisononyladipate (manufactured by J-PLUS Co., Ltd., DINA)in advance was added with respect to the total amount of thepolyisocyanate component and the first polyol component; and inSynthesis Example 12 (prepolymer (1)), a catalyst was not added, so thatthe resulting mixture was stirred and mixed under a temperature controlof 80° C. and a nitrogen gas stream, thereby obtaining prepolymers (a)to (1).

The concentration of the isocyanate group of each of the prepolymers (a)to (1) was measured by controlling the temperature to 80° C. The resultsare shown in Table 1.

The isocyanate group content was obtained by a titration method withdi-n-butylamine in conformity with the isocyanate group content ratiotest described in JIS K 7301.

TABLE 1 Synthesis Example No. Synthesis Ex. 1 Synthesis Ex. 2 SynthesisEx. 3 Synthesis Ex. 4 Synthesis Ex. 5 Isocyanate Group-terminated a b cd e Polyurethane Prepolymer Polyisocyanate 1,4-BIC (1) Trans 98%Component (3) Trans 94% (parts by mass) (4) Trans 86% 19.5 19.5 19.766.9 97.0 (5) Trans 73% (6) Trans 65% 1,3-BIC MDI First PolyolPLACCEL230N 100.0 100.0 100.0 Component PTG3000SN 100.0 (parts by mass)PEG#4000 100.0 Isocyanate Group Content (mass %) 4.65 4.63 4.75 15.6019.79 Synthesis Example No. Synthesis Ex. 6 Synthesis Ex. 7 SynthesisEx. 8 Synthesis Ex. 9 Synthesis Ex. 10 Isocyanate Group-terminated f g hi j Polyurethane Prepolymer Polyisocyanate 1,4-BIC (1) Trans 98% 66.9Component (3) Trans 94% 66.9 (parts by mass) (4) Trans 86% (5) Trans 73%19.5 (6) Trans 65% 19.5 1,3-BIC 80.4 MDI First Polyol PLACCEL 230N 100.0100.0 100.0 100.0 100.0 Component PTG3000SN (parts by mass) PEG#4000Isocyanate Group Content (mass %) 17.69 4.64 4.66 15.58 15.59 SynthesisExample No. Synthesis Ex. 11 Synthesis Ex. 12 Synthesis Ex. 13Isocyanate Group-terminated k l m Polyurethane Prepolymer Polyisocyanate1,4-BIC (1) Trans 98% Component (3) Trans 94% (parts by mass) (4) Trans86% 46.2 33.7 (5) Trans 73% (6) Trans 65% 1,3-BIC MDI 38.2 First PolyolPLACCEL230N 100.0 100.0 Component PTG3000SN 100.0 (parts by mass)PEG#4000 Isocyanate Group Content (mass %) 11.69 7.10 8.78

Description of Abbreviations in Table 1

1,4-BIC: 1,4-bis(isocyanatomethyl)cyclohexane produced in each ofProduction Examples

1,3-BIC: 1,3-bis(isocyanatomethyl)cyclohexane (trade name: TAKENATE600,manufactured by Mitsui Chemicals, Inc.)

MDI: diphenylmethane diisocyanate (trade name: COSMONATE PH,manufactured by Mitsui Chemicals & SKC Polyurethanes Inc.)

PLACCEL 230N: polycaprolactone diol (trade name: PLACCEL 230N, hydroxylvalue: 37.4 mgKOH/g, number average molecular weight: 3000, manufacturedby Daicel Corporation)

PTG3000SN: polytetramethylene ether glycol (trade name: PTG-3000SN,hydroxyl value: 37.5 mgKOH/g, number average molecular weight: 3000,manufactured by HODOGAYA CHEMICAL CO., LTD.)

PEG #4000: polyethylene glycol (trade name: PEG #4000, hydroxyl value:36.9 mgKOH/g, number average molecular weight: 3000, manufactured by NOFCORPORATION)

Production of Foaming Thermoplastic Polyurethane Resin Examples 1 to 15and 33, and Comparative Examples 1 to 5

The second polyol component (when the first polyol component wasblended, the first polyol component and the second polyol component) wasweighed in a stainless steel cup, so that in Examples 1 to 3, 5 to 15,and 33, and Comparative Examples 1 to 5 (foaming thermoplasticpolyurethane resins (A) to (C) and (E) to (W)), the ratio (NCO group/OHgroup, NCO index) of the isocyanate group (NCO group) in the prepolymerwith respect to the hydroxy group (OH group) in the second polyolcomponent (when the first polyol component is blended, the first polyolcomponent and the second polyol component) is 1.01, and in Example 4(foaming thermoplastic polyurethane resin (D)), the ratio thereof is1.03, and the temperature thereof was controlled to 80° C. With respectto the total amount of the prepolymer and the second polyol component(when the first polyol component is blended, the first polyol componentand the second polyol component), 0.3 mass % of IRGANOX 245(manufactured by BASF SE, heat resistant stabilizer), 0.25 mass % ofTINUVIN 234 (manufactured by BASF SE, ultraviolet absorber), and 0.15mass % of ADEKASTAB LA-72 (manufactured by ADEKA CORPORATION, lightresistant stabilizer (HALS)) were added into the prepolymer whosetemperature was controlled to 80° C. in a stainless steel vessel to bestirred and mixed for about 3 minutes by using a high-speed disper understirring of 500 to 1500 rpm. Next, the second polyol component (when thefirst polyol component was blended, the first polyol component and thesecond polyol component) whose temperature was controlled to 80° C. wasblended to be stirred and mixed for about 10 minutes by using ahigh-speed disper under stirring of 500 to 1500 rpm.

Next, a reaction liquid mixture was poured into a Teflon-made vat whosetemperature was controlled to 120° C. in advance to react at 120° C. for24 hours, so that primary products (A) to (O) and (R) to (W) wereobtained.

Thereafter, each of the primary products (A) to (O) and (R) to (W) wasremoved from the Teflon-made vat to be cut into cubes with a bale cutterand pulverized into a pulverized pellet with a pulverizing machine. Thepulverized pellet was left to stand at the heat treatment temperaturefor a heat treatment period described in Tables 2 to 6 to be dried at80° C. for a whole day and night under a nitrogen gas stream.Thereafter, the strand was extruded in a range of 150 to 270° C. of thecylinder temperature with a single screw extruder (type: SZW40-28MGCmanufactured by TECHNOVEL CORPORATION) to be cut, so that pellets of thefoaming thermoplastic polyurethane resins (A) to (0) and (R) to (W) wereobtained. The obtained pellets were further dried at 80° C. for a wholeday and night under a nitrogen gas stream.

The type, the mass ratio, the heat treatment temperature, and the heattreatment period of the prepolymer and the second polyol component (whenthe first polyol component is blended, the first polyol component andthe second polyol component) in Examples 1 to 15 and 33, and ComparativeExamples 1 to 5 are shown in Tables 2 to 6.

Evaluation of Foaming Thermoplastic Polyurethane Resin

The obtained foaming thermoplastic polyurethane resins (A) to (0) and(R) to (W) were evaluated by the following evaluation method. Theresults are shown in Tables 2 to 6.

(Weight Average Molecular Weight Measurement of Foaming ThermoplasticPolyurethane Resin with Gel Permeation Chromatography (GPC))

In a conical flask, 50 mg (sample) of foaming thermoplastic polyurethanewas immersed in 10 mL of N-methylpyrrolidone, and the temperature wascontrolled to 100° C. to be stirred by using a stirrer until the samplewas dissolved. Thereafter, the solution was cooled until a roomtemperature to be then filtrated by using a filtration filter of 0.45μm. Then, the filtrate was subjected to GPC measurement under thefollowing analysis conditions. Then, in the peak of the chromatogram,the ratio of the area corresponding to the high molecular weightcomponent having a weight average molecular weight of 400,000 or more tothe total area of the peak was calculated from the measuredchromatogram. The chromatogram obtained by the GPC measurement ofExample 2 and Comparative Example 1 is shown in FIG. 1.

Device: TOSOH HLC-8220GPC

Column: Shodex KF-805L×2 pieces+KF-G4 A (guard column)

Column temperature: 40° C.

Eluent: N-methylpyrrolidone (containing 50 mM of lithium bromide)

Flow: 0.7 mL/min

Sample concentration: 0.5 wt %

Injection amount: 100 μL

Detector: RI detector (differential refractometer)

Molecular weight marker: polystyrene (TSK gel standard polystyrene)

(Hard Segment Concentration of Foaming Thermoplastic Polyurethane Resin)

The hard segment (hard segment formed by reaction of the polyisocyanatecomponent with the second polyol component) concentration was calculatedfrom the mixing ratio (charging) of each of the components by thefollowing formula.Formula: [mass (g) of second polyol component+(mass (g) of second polyolcomponent/average molecular weight (g/mol) of second polyolcomponent)×average molecular weight (g/mol) of polyisocyanatecomponent]÷(mass (g) of first polyol component+polyisocyanate component(g)+mass (g) of second polyol component)×100

(Measurement of Aggregation Temperature of Foaming ThermoplasticPolyurethane Resin with Differential Scanning Calorimeter (DSC))

The measurement was performed by using a differential scanningcalorimeter (manufactured by SII NanoTechnology Inc., trade name:EXSTAR6000 PC Station and DSC220C). About 8 mg of foaming thermoplasticpolyurethane was thinly cut so as to have a shape capable of beingtightly in contact with an aluminum-made pan to be collected thereon.The aluminum-made pan was covered with a cover to be crimped, therebyobtaining a measurement sample (sample). The alumina was collected inthe same manner to be defined as a reference sample. The sample and thereference were set in a predetermined position in the cell; thereafter,the sample was cooled until −100° C. at a rate of 10° C./min under anitrogen gas stream of flow of 40 NmL/min to be retained at the sametemperature for 5 minutes; and next, the temperature thereof wasincreased to 270° C. at a rate of 10° C./min. Furthermore, after thesample was retained at 270° C. for 5 minutes, it was cooled until −70°C. at a rate of 10° C./min. The temperature of the exothermic peakappeared during this cooling was defined as the aggregation temperatureof the foaming thermoplastic polyurethane resin.

(Measurement of Hardness of Foaming Thermoplastic Polyurethane Resin)

The pellet of each of the foaming thermoplastic polyurethane resinsobtained in Examples 1 to 15 and 33, and Comparative Examples 1 to 5 wasinjection molded into a sheet shape by using an injection moldingmachine (type: NEX-140, manufactured by NISSEI PLASTIC INDUSTRIAL CO.,LTD.) at setting of a screw rotation number of 80 rpm and a barreltemperature of 150 to 270° C. under the conditions of a metal moldtemperature of 20° C., an injection time of 10 seconds, an injectionrate of 60 mm/s, and a cooling time of 20 to 60 seconds. After anobtained sheet having a thickness of 2 mm was subjected to annealtreatment for 3 days at an oven of 80° C., it was aged for 7 days underconstant temperature and constant humidity conditions of a roomtemperature of 23° C. and the relative humidity of 55%, so that anelastomer sheet of each of the foaming thermoplastic polyurethane resinsof Examples 1 to 15 and 33, and Comparative Examples 1 to 5 wasobtained.

The hardness (ASKER A and ASKER D) of each of the obtained elastomersheets was measured in conformity with “JIS K-7311 Test Method ofPolyurethane Thermoplastic Elastomer” (1995).

Production of Polyurethane Foaming Molded Article

As described in the following, polyurethane foaming molded articles (A)to (W) were obtained from the foaming thermoplastic polyurethane resinsof Examples 1 to 15 and 33, and Comparative Examples 1 to 5.

The melt viscosity and the outflow starting temperature (flow startingtemperature) of the foaming thermoplastic polyurethane resin weremeasured as described in the following.

(Measurement of Melt Viscosity and Flow Starting Temperature)

The flow starting temperature was measured by using a Koka-type flowtester (manufactured by Shimadzu Corporation, type: Shimadzu flow testerCFT-500), the temperature lower than the flow starting temperature by20° C. was defined as the measurement starting temperature, and the meltviscosity was measured at a load of 196N and the temperature rising rateof 2.5° C./min. As the foaming thermoplastic polyurethane resin used inthe measurement, one that dried at 80° C. for a whole day and nightunder a nitrogen gas stream was used.

Examples 16 to 30 and 34, and Comparative Examples 6 to 10 (Molding byExtrusion Foaming Method using Supercritical Carbon Dioxide)

Polyurethane foaming molded articles (A) to (O) and (R) to (W) weremolded from the foaming thermoplastic polyurethane resins (A) to (O) and(R) to (W) by an extrusion foaming method using the supercritical carbondioxide.

To be specific, a single screw extruder having a diameter of 30 mm in afirst step (manufactured by Sun Engineering Co., Ltd., backflowpreventing-type supercritical carbon dioxide gas injection port was setat a position of L/D=32 and L/D=17.5) was connected to an extruder(manufactured by Sun Engineering Co., Ltd., L/D=42) having a diameter of40 mm in a second step with a short tube (hereinafter, referred to as aconnection) having a diameter of 10 mm, and a tandem extruder equippedwith a circular die (lip diameter (diameter): 40 mm, gap between the lipand the core: 0.46 mm) at the front end portion of the extruder (secondstep) having a diameter of 40 mm was used.

The barrel temperature of the single screw extruder having a diameter of30 mm in the first step was set at the temperature where the meltviscosity of the foaming thermoplastic polyurethane resin showed 1000Pa-s, and the set temperature of the extruder having a diameter of 40 mmin the second step was set at the flow starting temperature of thefoaming thermoplastic polyurethane resin.

After the foaming thermoplastic polyurethane resin dried for a whole dayand night in the oven at 80° C. under a nitrogen gas stream wassufficiently melted by using a single screw extruder (screw rotationnumber: 30 rpm) having a diameter of 30 mm in the first step, thesupercritical carbon dioxide obtained by increasing a pressure until 30MPa from a liquefied carbon dioxide cylinder through a pressure boostingdevice (SCF-Get manufactured by JASCO Corporation) was suppled to themelted foaming thermoplastic polyurethane resin at a flow rate of 25g/hour to be sufficiently kneaded and melted, so that a kneaded productwas produced.

Subsequently, the kneaded product was sent through the connection intothe extruder (screw rotation number: 4 μm) having a diameter of 40 mm inthe second step, and when the state of the kneaded product (foamingbody) discharged from the circular die was stable, the air was sent intothe inside of a cylindrical foaming body to be cooled, so that thecylindrical foaming body having a thickness of 2 mm was obtained. Thecircumference of the foaming body was cut to be expanded in a dischargeddirection, so that polyurethane foaming molded articles (A) to (O) and(R) to (W) in a sheet shape having a thickness of 2 mm were obtained.

Example 31 (Molding by Injection Foaming Method Using SupercriticalCarbon Dioxide)

A polyurethane foaming molded article (P) was molded from the foamingthermoplastic polyurethane resin (B) by the injection foaming methodusing the supercritical carbon dioxide.

To be specific, the foaming thermoplastic polyurethane resin (B) driedfor a whole day and night in the oven at 80° C. under a nitrogen gasstream was charged into an injection molding machine (type: JSW MuCell110H/J85AD, manufactured by The Japan Steel Works, LTD.) where thebarrel temperature was set at the temperature in which the meltviscosity of the foaming thermoplastic polyurethane resin showed 1000Pa·s, and the supercritical carbon dioxide obtained by increasing apressure until 30 MPa through a pressure boosting device (SCF-Getmanufactured by JASCO Corporation) at the time of measurement was sentinto the foaming thermoplastic polyurethane resin at a ratio of 0.8 mass% to be kneaded.

After the injection was conducted in a metal mold set at 60° C. andhaving a thickness of 1.5 mm at an injection rate of 60 mm/min, aholding pressure of 50 MPa, and a holding time of 5 seconds, the metalmold core receded by 4.5 mm and after cooling for 60 seconds, apolyurethane foaming molded article (P) having a thickness of 6 mm wasobtained by demolding.

Example 32 (Molding by Bead Foaming Method)

A polyurethane foaming body (Q) was molded from the foamingthermoplastic polyurethane resin (B) by a bead foaming method using thesupercritical carbon dioxide.

To be specific, a single screw extruder having a diameter of 30 mm in afirst step (manufactured by Sun Engineering Co., Ltd., backflowpreventing-type supercritical carbon dioxide gas injection port was setat a position of L/D=32 and L/D=17.5) was connected to an extruder(manufactured by Sun Engineering Co., Ltd., L/D=42) having a diameter of40 mm in a second step with the connection having a diameter of 10 mm,and a tandem extruder equipped with a dice of a singular hole (diameterof the hole: 1.5 mm) at the front end portion of the extruder (secondstep) having a diameter of 40 mm was used.

The barrel temperature of the single screw extruder having a diameter of30 mm in the first step was set at the temperature where the meltviscosity of the foaming thermoplastic polyurethane resin showed 1000Pa-s, and the set temperature of the extruder having a diameter of 40 mmin the second step was set at the flow starting temperature of thefoaming thermoplastic polyurethane resin.

After the foaming thermoplastic polyurethane resin (B) dried for a wholeday and night in the oven at 80° C. under a nitrogen gas stream wassufficiently melted by using a single screw extruder (screw rotationnumber: 30 rpm) having a diameter of 30 mm in the first step, thesupercritical carbon dioxide obtained by increasing a pressure until 30MPa from a liquefied carbon dioxide cylinder through a pressure boostingdevice (SCF-Get manufactured by JASCO Corporation) was suppled to themelted foaming thermoplastic polyurethane resin at a flow rate of 25g/hour to be sufficiently kneaded and melted, so that a kneaded productwas produced.

Subsequently, the kneaded product was sent through the connection intothe extruder (screw rotation number: 4 μm) having a diameter of 40 mm inthe second step, and when the kneaded product (foaming body strand)discharged from the dice was cooled and the state of the foaming bodystrand was stable, the foaming body was cut into a piece having anappropriate size (about 2 mm in size), so that a foaming bead wasobtained.

Thereafter, the foaming bead was charged into the metal mold, and thetemperature thereof was controlled at a pressure of 1 MPa with vapor at180° C. to be then cooled, so that a polyurethane foaming molded article(Q) having a thickness of 6 mm was obtained.

Evaluation of Polyurethane Foaming Molded Article

The obtained polyurethane foaming molded articles (A) to (W) wereevaluated by the following evaluation method. The results are shown inTables 2 to 6.

(Uniformity of Cell)

The uniformity of the cell of the obtained polyurethane foaming moldedarticle was visually observed, and evaluations 5 to 1 were set asdescribed in the following to be evaluated by 5 steps.

Evaluation 5: Most of the cells are minute, and the size of the cells isalmost uniform.

Evaluation 4: Coarse cells are few, and the size of the cells is almostuniform.

Evaluation 3: Coarse cells are few, but the size of the cells is notuniform.

Evaluation 2: Coarse cells are many, and the size of the cells is notuniform.

Evaluation 1: Most of the cells are coarse, and the size of the cells isnot uniform.

(Core Density (unit: kg/m³))

A rectangular parallelepiped having a size of 10 cm×10 cm was cut fromthe obtained polyurethane foaming molded article, so that a measurementsample was produced.

Thereafter, the apparent density of the measurement sample was measuredin conformity with JIS K 7222 (2005). This obtained result was evaluatedas the core density (apparent core density) of the polyurethane foamingmolded article.

(Hardness (ASKER C))

The obtained polyurethane foaming molded articles were stacked so as tohave a thickness of 12 mm, and the C hardness thereof was measured inconformity with the hardness test (type C) of JIS K 7312 (1996).

(Rebound Resilience (Unit: %))

After a rectangular parallelepiped having a size of 10 cm×10 cm was cutfrom the obtained polyurethane foaming molded article, the rectangularparallelepipeds were stacked so as to have a thickness of 12 mm toobtain a measurement sample.

The rebound resilience of the measurement sample was measured inconformity with JIS K 6400-3 (2004).

(Compression Permanent Set (Unit: %))

After the obtained polyurethane foaming molded article was cut intopiece in a columnar shape having a diameter of 29 mm, a measurementsample was produced so as to have a thickness of 12 mm.

Thereafter, the compression permanent set of the measurement sample wasmeasured under the conditions of 23° C. and a compression of 25% inconformity with JIS K 6262.

(Breaking Strength (Unit: MPa))

A measurement sample was produced from the obtained polyurethane foamingmolded article by using a JIS No. 1 dumbbell, and thereafter, thebreaking strength of the measurement sample was measured in conformitywith JIS K 6400-5 (2012).

(Tear Strength (Unit: kN/m))

A measurement sample was produced from the obtained polyurethane foamingmolded article by using a JIS B-type dumbbell, and thereafter, the tearstrength of the measurement sample was measured in conformity with a Bmethod of JIS K 6400-5 (2012).

(Initial Color Phase: b*. Resistance to Discoloration by UltravioletLight (UV): Δb)

A rectangular parallelepiped having a size of 30 mm×40 mm was cut fromthe polyurethane foaming molded article, so that a measurement samplewas produced. The yellowness b* thereof was measured by using a colordifference meter (manufactured by Tokyo Denshoku Co., Ltd., Color AceModel TC-1), b* is generally defined as a reference of the color phaseof polyurethane.

Thereafter, an ultraviolet light of a short wavelength (wavelength of270 to 720 mm) was applied to the measurement sample for 24 hours byusing a QUV weathering tester equipped with an ultraviolet fluorescent(manufactured by Suga Test Instruments Co., Ltd., ultravioletfluorescent weather meter FUV).

Δb (amount of change of b value) of the polyurethane foaming moldedarticle before and after the application of ultraviolet light wasmeasured by using the color difference meter (manufactured by TokyoDenshoku Co., Ltd., Color Ace Model TC-1). Δb is generally defined as areference of the resistance to discoloration by UV of the foaming moldedarticle.

TABLE 2 Example No. Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Foaming ThermoplasticPolyurethane Resin A B C D E Type of Prepolymer a a b c a Second PolyolComponent (parts 1,4-BD 4.9 4.9 4.9 4.9 4.9 by mass to 100 parts by massof Prepolymer) First Polyol Component (parts by PLACCEL mass to 100parts by mass of 230N Prepolymer) Hard Segment Concentration (mass %) 1515 15 15 15 Heat Treatment Temperature (° C.) 80 80 80 80 80 HeatTreatment Period (day) 4 7 7 7 10 Area Ratio (%) of Area of HighMolecular 29 45 47 44 57 Weight Component Having Weight AverageMolecular Weight of 400,000 or more to Total Area of Peak inChromatogram Aggregation Temperature (° C.) 133 135 140 141 135 Hardnessof Foaming Thermoplastic 81A 81A 81A 82A 81A Polyurethane Resin ExampleNo. Ex. 16 Ex. 17 Ex. 18 Ex. 19 Ex. 20 Polyurethane Foaming MoldedArticle A B C D E Molding Method of Polyurethane Extrusion ExtrusionExtrusion Extrusion Extrusion Foaming Molded Article Foaming FoamingFoaming Foaming Foaming Evaluation Uniformity of Cell 4 5 5 5 4 CoreDensity (g/cm³) 0.27 0.25 0.24 0.24 0.28 Hardness (ASKER C) 42C 40C 36C38C 43C Rebound Resilience (%) 72 74 78 76 71 Compression Permanent Set(%) 13 9 10 10 12 Breaking Strength (MPa) 2.1 2.5 2.4 2.3 2.2 TearStrength (kN/m) 9.8 11.3 10.4 10.7 9.5 Initial Color Phase (b*) 1.4 1.51.7 1.8 1.9 Resistance to Discoloration by 1.7 1.9 2.1 2.0 2.7Ultraviolet Light (Δb)

TABLE 3 Example No. Ex. 6 Ex. 7 Ex. 8 Ex. 9 Ex. 10 Foaming ThermoplasticPolyurethane Resin F G H I J Type of Prepolymer a a d e f Second PolyolComponent (parts 1,4-BD 1.9 2.8 16.6 21.0 18.8 by mass to 100 parts bymass of Prepolymer) First Polyol Component (parts by PLACCEL 101.4 72.9mass to 100 parts by mass of 230N Prepolymer) Hard Segment Concentration(mass %) 3 5 45 55 50 Heat Treatment Temperature (° C.) 80 80 80 80 80Heat Treatment Period (day) 7 7 7 7 7 Area Ratio (%) of Area of HighMolecular 47 46 40 39 39 Weight Component Having Weight AverageMolecular Weight of 400,000 or more to Total Area of Peak inChromatogram Aggregation Temperature (° C.) 83 98 175 186 No DetectionHardness of Foaming Thermoplastic 68A 72A 50D 60D 80A Polyurethane ResinExample No. Ex. 21 Ex. 22 Ex. 23 Ex. 24 Ex. 25 Polyurethane FoamingMolded Article F G H I J Molding Method of Polyurethane ExtrusionExtrusion Extrusion Extrusion Extrusion Foaming Molded Article FoamingFoaming Foaming Foaming Foaming Evaluation Uniformity of Cell 4 5 5 4 4Core Density (g/cm³) 0.27 0.26 0.27 0.28 0.29 Hardness (ASKER C) 29C 31C51C 60C 39C Rebound Resilience (%) 75.0 79.0 69.0 61.0 53.0 CompressionPermanent Set (%) 11 6 11 14 17 Breaking Strength (MPa) 1.5 2.0 3.8 3.01.3 Tear Strength (kN/m) 6.8 8.4 15.5 12.9 7.1 Initial Color Phase (b*)1.3 1.4 1.7 1.8 2.1 Resistance to Discoloration by 1.8 2.1 2.4 2.6 3.5Ultraviolet Light (Δb)

TABLE 4 Example No. Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 15 FoamingThermoplastic Polyurethane Resin K L M N O Type of Prepolymer g h i j kSecond Polyol Component (parts 1,4-BD 4.9 4.9 16.5 16.6 12.4 by mass to100 parts by mass of Prepolymer) First Polyol Component (parts PLACCELby mass to 100 parts by mass of 230N Prepolymer) Hard SegmentConcentration (mass %) 15 15 45 45 35 Heat Treatment Temperature (° C.)80 80 80 80 80 Heat Treatment Period (day) 7 7 7 7 7 Area Ratio (%) ofArea of High Molecular 40 42 45 44 47 Weight Component Having WeightAverage Molecular Weight of 400,000 or more to Total Area of Peak inChromatogram Aggregation Temperature (° C.) 78 94 178 184 167 Hardnessof Foaming Thermoplastic 70A 74A 54D 56D 95A Polyurethane Resin ExampleNo. Ex. 26 Ex. 27 Ex. 28 Ex. 29 Ex. 30 Polyurethane Foaming MoldedArticle K L M N O Molding Method of Polyurethane Extrusion ExtrusionExtrusion Extrusion Extrusion Foaming Molded Article Foaming FoamingFoaming Foaming Foaming Evaluation Uniformity of Cell 4 5 5 4 5 CoreDensity (g/cm³) 0.29 0.27 0.27 0.28 0.25 Hardness (ASKER C) 33C 34C 55C57C 46C Rebound Resilience (%) 62 70 68 63 71 Compression Permanent Set(%) 12 7 12 15 11 Breaking Strength (MPa) 1.8 2.2 4.0 3.5 3.3 TearStrength (kN/m) 8.6 9.8 15.8 13.5 14.4 Initial Color Phase (b*) 1.7 1.61.6 1.8 1.5 Resistance to Discoloration by 3.2 2.6 2.0 1.8 2.4Ultraviolet Light (Δb)

TABLE 5 Example No. — — Ex. 33 Foaming Thermoplastic Polyurethane ResinB B W Type of Prepolymer a a m Second Polyol Component 1,4-BD 4.9 4.99.3 (parts by mass to 100 parts by mass of Prepolymer) First PolyolComponent PLACCEL (parts by mass to 100 parts 230N by mass ofPrepolymer) Hard Segment Concentration (mass %) 15 15 27 Heat TreatmentTemperature (° C.) 80 80 80 Heat Treatment Period (day) 7 7 7 Area Ratio(%) of Area of High Molecular 45 45 48 Weight Component Having WeightAverage Molecular Weight of 400,000 or more to Total Area of Peak inChromatogram Aggregation Temperature (° C.) 135 135 147 Hardness ofroaming Thermoplastic Polyurethane 81A 81A 90A Resin Example No. Ex. 31Ex. 32 Ex. 34 Polyurethane Foaming P Q W Molded Article Molding Methodof Polyurethane Injection Foaming Extrusion Foaming Molded ArticleFoaming Bead Foaming Evaluation Uniformity of Cell 5 5 5 Core Density(g/cm³) 0.26 0.25 0.25 Hardness (ASKER C) 39C 40C 42C Rebound Resilience(%) 75 73 79 Compression Permanent 10 15 9 Set (%) Breaking Strength(MPa) 2.3 2.0 3.0 Tear Strength (kN/m) 11.0 10.6 12.5 Initial ColorPhase (b*) 1.6 1.7 1.6 Resistance to 1.9 2.5 2.2 Discoloration byUltraviolet Light (Δb)

TABLE 6 Example No. Comp. Ex. 1 Comp. Ex. 2 Comp. Ex. 3 Comp. Ex. 4Comp. Ex. 5 Foaming Thermoplastic Polyurethane Resin R S T U V Type ofPrepolymer a a a a l Second Polyol Component (parts 1,4-BD 4.9 4.9 4.94.9 7.5 by mass to 100 parts by mass of Prepolymer) First PolyolComponent (parts PLACCEL by mass to 100 parts by mass of 230NPrepolymer) Hard Segment Concentration (mass %) 15 15 15 15 27 HeatTreatment Temperature (° C.) 80 80 25 110 80 Heat Treatment Period (day)2 15 7 5 3 Area Ratio (%) of Area of High Molecular 23 63 19 67 35Weight Component Having Weight Average Molecular Weight of 400,000 ormore to Total Area of Peak in Chromatogram Aggregation Temperature (°C.) 125 133 123 124 81 Hardness of Foaming Thermoplastic 80A 81A 79A 82A82A Polyurethane Resin Example No. Comp. Ex. 6 Comp. Ex. 7 Comp. Ex. 8Comp. Ex. 9 Comp. Ex. 10 Polyurethane Foaming Molded Article R S T U VMolding Method of Polyurethane Extrusion Extrusion Extrusion ExtrusionExtrusion Foaming Molded Article Foaming Foaming Foaming Foaming FoamingEvaluation Uniformity of Cell 2 2 1 2 3 Core Density (g/cm³) 0.29 0.310.29 0.28 0.26 Hardness (ASKER C) 45C 46C 42C 43C 41C Rebound Resilience(%) 58 63 59 71 53 Compression Permanent Set (%) 25 24 26 24 27 BreakingStrength (MPa) 1.4 1.6 1.2 1.6 1.5 Tear Strength (kN/m) 6.9 7.4 6.2 7.78.4 Initial Color Phase (b*) 1.5 4.5 1.4 5.8 9.5 Resistance toDiscoloration by 2.0 4.1 2.2 5.1 15.0 Ultraviolet Light (Δb)

Description of Abbreviations in Tables 2 to 6

Prepolymer: isocyanate group-terminated polyurethane prepolymer

1,4-BD: 1,4-butanediol (manufactured by Mitsubishi Chemical Corporation)

PLACCEL 230N: polycaprolactone polyol (trade name: PLACCEL 230N,hydroxyl value: 37.4 mgKOH/g, number average molecular weight: 3000,manufactured by Daicel Corporation)

Uses of Polyurethane Foaming Molded Article Reference Example 1

By using the foaming thermoplastic polyurethane resin (B), apolyurethane foaming molded article for a midsole having the density of0.25 g/cm³ was molded by injection foaming in the same manner as that ofExample 31.

A test piece in a strip shape having a width of 10 mm and a length of 12cm was stamped out from the foaming molded article, and Demattia FlexCracking Test was repeatedly conducted under the conditions of 23° C.and a frequency of 5 Hz. As a result, there was no crack with a test of150,000 times or more.

Reference Example 2

By using the foaming thermoplastic polyurethane resin (B), apolyurethane foaming molded article for a shock absorber having thedensity of 0.50 g/cm³ was molded by injection foaming in the same manneras that of Example 31.

A test piece of the foaming molded article in a columnar shape having adiameter of 29 mm and a height of 30 mm was repeatedly subjected to acompression test at a compression rate of 75% under the conditions of23° C. and a frequency of 0.22 Hz. As a result, there was no crack witha test of 2500 times or more.

Reference Example 3

By using the foaming thermoplastic polyurethane resin (B), apolyurethane foaming molded article for a chemical mechanical polishing(CMP) pad having the density of 0.30 g/cm³ was molded by injectionfoaming in the same manner as that of Example 31.

The foaming molded article was stamped out in a circular shape(thickness of 3 mm) having a diameter of 50 mm to be immersed in butylacetate and methyl ethyl ketone at 23° C. for 7 days, so that the volumechange ratio ((V1 (volume after immersion)−V0 (volume beforeimmersion))/V0×100(%)) was calculated. The results were 55% and 70%,respectively.

Reference Example 4

By using the foaming thermoplastic polyurethane resin (B), apolyurethane foaming molded article for an automobile interior memberhaving the density of 0.15 g/cm³ was molded by injection foaming in thesame manner as that of Example 31. The foaming molded article wasstamped out in a circular shape (thickness of 3 mm) having a diameter of50 mm to be immersed in oleate at 23° C. for 7 days, so that the volumechange ratio ((V1 (volume after immersion)−V0 (volume beforeimmersion))/V0×100(%)) was calculated. The result was 7%.

While the illustrative embodiments of the present invention are providedin the above description, such is for illustrative purpose only and itis not to be construed as limiting the scope of the present invention.Modification and variation of the present invention that will be obviousto those skilled in the art is to be covered by the following claims.

INDUSTRIAL APPLICABILITY

The foaming thermoplastic polyurethane resin, the producing methodthereof, and the molded article of the present invention are preferablyused as a midsole, a shock absorber, a chemical mechanical polishing(CMP) pad, sports articles, an automobile interior member, or the like.

The invention claimed is:
 1. A foamable thermoplastic polyurethane resinwhich is: a reaction product of a polyisocyanate component containing abis(isocyanatomethyl)cyclohexane and a polyol component, wherein in apeak of a chromatogram obtained by measurement of the foamablethermoplastic polyurethane resin with gel permeation chromatography, thearea of a high molecular weight component having a weight averagemolecular weight of 400,000 or more with respect to the total area ofthe peak is 29% to 60%.
 2. The foamable thermoplastic polyurethane resinaccording to claim 1, wherein an aggregation temperature of the foamablethermoplastic polyurethane resin measured with a differential scanningcalorimeter is 90° C. to 180° C.
 3. The foamable thermoplasticpolyurethane resin according to claim 1, wherein thebis(isocyanatomethyl)cyclohexane is a1,4-bis(isocyanatomethyl)cyclohexane.
 4. The foamable thermoplasticpolyurethane resin according to claim 3, wherein the1,4-bis(isocyanatomethyl)cyclohexane contains a trans-isomer at a ratioof 70 mol % to 96 mol %.
 5. A method for producing a foamablethermoplastic polyurethane resin comprising: a reaction step ofobtaining a primary product by allowing a polyisocyanate componentcontaining a bis(isocyanatomethyl)cyclohexane to react with a polyolcomponent and a heat treatment step of, after the reaction step, heattreating the primary product at 50° C. to 100° C. for 4 days to 10 days.6. A molded article comprising: the foamable thermoplastic polyurethaneresin according to claim
 1. 7. The molded article according to claim 6,wherein the molded article is a midsole.
 8. The molded article accordingto claim 6, wherein the molded article functions as a shock absorber. 9.The molded article according to claim 6, wherein the molded article is achemical mechanical polishing pad.
 10. The molded article according toclaim 6, wherein the molded article is an automobile interior part.